圆形Button

  using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Drawing;using System.Windows.Forms;using System.Windows.Forms.VisualStyles;namespace StudyWinForm1{ class MyEllipseButton:Button { //state variable for mouse downprivate bool mouseDown=false;//state variable for mouse hoverprivate bool mouseHover=false; public MyEllipseButton(){ //set the control UserPaint SetStyle(ControlStyles.UserPaint, true); //EventHandler for MouseDown MouseDown += new MouseEventHandler(OnMouseDown); //EventHandler for MouseUp MouseUp += new MouseEventHandler(OnMouseUp); //EventHandler for MouseEnter MouseEnter += new EventHandler(OnMouseEnter); //EventHandler for MouseLeave MouseLeave += new EventHandler(OnMouseLeave); Height = 23;//Default Height Width = 75;//Default Width //set the back color to blue BackColor = System.Drawing.Color.Blue; //set the appearance style to flat FlatStyle = System.Windows.Forms.FlatStyle.Flat; //use system default font Font = System.Windows.Forms.Control.DefaultFont; //use white color to write text and draw the border ForeColor = System.Drawing.Color.White;}protected override void OnPaint(PaintEventArgs pe){//first, paint the control with parent form's background color pe.Graphics.FillRectangle(new SolidBrush(Parent.BackColor), pe.ClipRectangle); //pe.Graphics.FillEllipse(new SolidBrush(Parent.BackColor),pe.ClipRectangle);//if the button is disabled, draw the disable styleif (Enabled == false){DrawDisableButton(pe.Graphics);}else if (mouseDown){//when mouse down, draw the mouse down styleDrawMouseDownButton(pe.Graphics);}else if (mouseHover){//when mouse hover, draw the mouse hover styleDrawMouseHoverButton(pe.Graphics);}else if (Focused){//when mouse is focused but not mouse hover,//draw the focus styleDrawContainFocusButton(pe.Graphics);} else//else, draw the normal style{DrawNormalButton(pe.Graphics);}WriteText(pe.Graphics);//write text}private void OnMouseDown(object sender,MouseEventArgs e){mouseDown=true;//mouse is down now}private void OnMouseUp(object sender,MouseEventArgs e){mouseDown=false;//mouse is up now//call paint actionPaintEventArgs pe = new PaintEventArgs(CreateGraphics(), ClientRectangle);OnPaint(pe);}private void OnMouseEnter(object sender,EventArgs e){mouseHover=true;//mouse hover on//call paint actionPaintEventArgs pe = new PaintEventArgs(CreateGraphics(),ClientRectangle);OnPaint(pe);}private void OnMouseLeave(object sender,EventArgs e){mouseHover=false;//mouse is not hover on//call paint actionPaintEventArgs pe = new PaintEventArgs(CreateGraphics(),ClientRectangle);OnPaint(pe);}private void DrawBorder(Graphics g,int state){if (state==1)//draw normal style broder{ Pen p = new Pen(System.Drawing.SystemColors.ControlLightLight, 2); g.DrawEllipse(p, 0, 0, Width - 6, Height - 6);}else if (state==2)//draw hover style border{Pen p = new Pen(Color.Yellow,2); g.DrawEllipse(p, 0, 0, Width - 7, Height - 7);}else if (state==3)//draw pressed style border{ Pen p = new Pen(System.Drawing.SystemColors.ControlDark, 2); g.DrawEllipse(p, 0, 0, Width - 7, Height - 7);}else if (state==4)//draw disabled style border{ Pen p = new Pen(System.Drawing.SystemColors.ControlLight, 2); g.DrawEllipse(p, 0, 0, Width - 7, Height - 7);}else if (state==5)//draw default style border{Pen p = new Pen(Color.SkyBlue,2); g.DrawEllipse(p, 0, 0, Width - 7, Height - 7);}if (state==4)//draw disable style border{Pen p = new Pen(Color.FromArgb(161,161,146),1); g.DrawEllipse(p, 0, 0, Width - 6, Height - 6); g.DrawEllipse(p, 1, 1, Width - 7, Height - 7);}else//draw normal style border{ g.DrawEllipse(Pens.Black, 0, 0, Width - 6, Height - 6); g.DrawEllipse(Pens.Black, 1, 1, Width - 7, Height - 7);}}private void DrawNormalButton(Graphics g)//draw normal style button{//draw normal style borderDrawBorder(g,1);//paint background //PaintBack(g, System.Drawing.SystemColors.ControlLightLight); PaintBack(g, Color.Yellow);}private void DrawMouseHoverButton(Graphics g){//draw mouse hover style borderDrawBorder(g,2);//paint background //PaintBack(g, System.Drawing.SystemColors.ControlLightLight); PaintBack(g, Color.Violet);}private void DrawMouseDownButton(Graphics g){//draw mouse down style borderDrawBorder(g,3);//paint background //PaintBack(g, System.Drawing.SystemColors.ControlLight); PaintBack(g, Color.Tomato);}private void DrawDisableButton(Graphics g){//draw disable style borderDrawBorder(g,4);//paint background //PaintBack(g, System.Drawing.SystemColors.ControlLight); PaintBack(g, Color.Transparent);}private void DrawContainFocusButton(Graphics g){//draw contain focuse style borderDrawBorder(g,5);//paint background //PaintBack(g, System.Drawing.SystemColors.ControlLightLight); PaintBack(g, Color.Turquoise);}//paint background area of the buttonprivate void PaintBack(Graphics g,Color c){ //g.FillRectangle(new SolidBrush(c), 3, 3, Width - 6, Height - 6); g.FillEllipse(new SolidBrush(c), 0, 0, Width - 6, Height - 6); }private void WriteText(Graphics g){//calculate the text positionint x=0,y=0; System.Drawing.Size s = g.MeasureString(Text, Font).ToSize();x=(Width-s.Width)/2;y=(Height-s.Height)/2;//draw textif (Enabled) //is enabled, draw black textg.DrawString(Text,Font,Brushes.Black,x,y);else //not enabled, draw gray textg.DrawString(Text,Font,Brushes.Gray,x,y);} }}